A ten-year-old has passed away after the boat she was riding in on Chickamauga Lake overturned during severe weather Thursday evening.

Thursday's storms claimed the lives of a 10-year-old girl and her grandmother when the boat they were in overturned on Chickamauga Lake, Tennessee Wildlife Resources Agency spokesman Dan Hicks said.

Twelve people were on the pontoon boat when it flipped during high winds. The girl and her grandmother were trapped under the boat for eight to 10 minutes, witnesses said.

Witnesses helped pull people out of the water, using boats and Jet Skis. Local stockbroker Mike Brown and his son, Michael, took their boat to the scene, Debbie Brown said in an email. She said they pulled the child and grandmother from the water.

"I called 911, but it took forever for the paramedics," she wrote. "Our neighbors took turns giving CPR. We just wish we could have gotten to them faster, but Mike did all he could to get the boat out to them in the storm."

Hicks said the boat was a 30-foot, double-decker pontoon boat. All the children on the boat were wearing life jackets, he said. The boat was heading for shore to try to avoid the storm when it flipped, TWRA officials said.

The accident happened at Pumphouse Slough, near Island Cove Marina.